You’re probably already familiar with this commonly produced coffee bean; it accounts for over 60% of the world’s coffee production. Arabica beans are grown at high altitudes, in areas that receive steady rainfall and have a plentiful amount of shade. Arabica trees are generally easy to care for as they are relatively small and easy to prune—they are normally no taller than 6′; their small stature also makes harvesting simpler.
Arabica is the most delicate of the 4. It is easily influenced by its environment and prone to disease. It must be farmed with great care. When Arabica plants are grown in climates where they do not naturally thrive, it can take double the effort to keep them healthy. Since it is one of the more popular beans, Arabica is often grown in large quantities (called “monoculture”)—however, this has the potential for disaster. Growing the disease-prone Arabica plants in large groups makes the trees more susceptible to a massive outbreak of disease, such as blight, that will inevitably contaminate the entire crop. If one Arabica plant goes, there’s a solid chance a large portion of the crop is going with it.
Higher quality Arabica beans have a bright body, possess a satisfying amount of acidity, and tend to have a multi-layered intricacy of flavors and aromas; Arabica coffees can be best sampled on the front palate (where sweetness and salinity are most apparent). For best results when brewing this coffee at home, look for Arabica coffee that has a full body and lower acidity.
Note that the quality of the Arabica bean diminishes when served cold or with creamer. It is best served hot, perhaps brewed with the pour-over or drip coffee technique.
Robusta (Coffea caniphora)
You’ve also probably heard of Robusta as it comes second to Arabica as the world’s most produced coffee.
Its name is no coincidence. The Robusta varietal is extremely tolerant of its environment and practically immune to disease. Robusta coffee can withstand myriad altitudes, but particularly requires a hot climate where rainfall is irregular. Robusta coffee beans have almost double the amount of caffeine compared to Arabica beans—in fact, caffeine is what makes Robusta plants so robust! Caffeine is the plant’s self-defense against disease.
When drinking, Robusta coffee is best sampled on the back palate (where bitter notes are most apparent), which gives it a heavier body. Higher quality Robusta beans have a smooth texture, low acidity, and often have hints of chocolate associated with their flavor profile. For the best tasting experience when brewing at home, buy Robusta coffee that has information on the way it was grown—this is often information provided on bags of single-origin coffee — as many times, farmers try to take advantage of Robusta’s popularity and grow the bean in unfavourable climates, producing a sub-standard product; if your Robusta has a flat smell or rubbery taste, your coffee has been a victim of these practices.
This is a perfect coffee for cream and sugar lovers! A good quality Robusta will not lose flavor when adding milk or sugar (making it a great candidate for Vietnamese Coffee and Iced Coffee).
Liberica (Coffea liberica)
Liberica is harder to come by in the coffee world these days, but this varietal has an important place in the world’s coffee history.
In 1890, coffee rust decimated over 90% of the world’s Arabica stock. Scrambling to find a solution, farmers and government agents alike turned to the Liberica plant; the first country to try this was the Philippines (which was a U.S. territory at the time). This decision greatly helped the Philippines’ economy as they were the only coffee supplier for a time.
However, a spat between the U.S. and the Philippines (over the country declaring independence) broke out; this led to the U.S. cutting supplies off, including coffee, to the archipelago. It wasn’t until 1995 that Liberica made an appearance in the coffee world again; conservationists salvaged the last remaining plants by transplanting them in Filipino growing regions better suited for Liberica to thrive. Sadly, this effort was too little too late as Arabica wore the crown (that it still wears today) as the reigning coffee varietal of the world by the time the crop was ready for harvest. Its absence can still be felt today as it grows harder and harder to come by pure Liberica coffee.
Liberica beans are larger than the others, often asymmetrical, and they’re the only coffee bean in the world that has such an irregular shape. The beans are said to have a unique aroma, consisting of floral and fruity notes, with a full body that possesses a smoky taste; those who have had Liberica coffee say that it is unlike any coffee they have ever tasted—with many saying it does not even taste like coffee, stating that it tastes too “woody”.
Excelsa (Coffea excelsa)
Although Excelsa has been recently re-classified as a member of the Liberica family, the two couldn’t be more different; it differs so much from Liberica that some members of the coffee community still think of it as a separate species. It was re-named as a genus of Liberica because it grows on large 20-30 ft trees like Liberica at similar altitudes and has a similar almond-like shape.
Excelsa grows mostly in Southeast Asia and accounts for a mere 7% of the world’s coffee circulation. It is largely used in blends in order to give the coffee an extra boost of flavor and complexity, better affecting the middle and back palate. Excelsa is said to possess a tart and fruity body—which are flavors reminiscent of a light roast—that also somehow has dark, roasty notes. This mystery lures coffee drinkers from around the world to try and seek out the varietal.